If you use the auto setup and run audyssey then the denon will automatically adjust channel levels during the set up... there is no need to touch the volume knob.

If you manually calibrate then just adjust the channel levels and not the main volume as well. I left the main volume at 0 db (its default posistion in the manual setup menu for the denon) during the entire manual set up and just adjusted the individual channel levels.

-David